The rates of patients with ACTN4 CNI seem comparable to those of high-risk patients categorised by the 21-gene recurrence score (31 or higher).7 The NSABP B-20 prospective-retrospective study revealed that addition of chemotherapy to tamoxifen had therapeutic benefits for patients with node-negative, ER-positive breast cancer with a 21-gene recurrence score of ≥31,26 indicating that patients with node-negative luminal breast cancer carrying ACTN4 CNI might similarly benefit from postoperative adjuvant chemotherapy. The gene discussed is ACTN4; the disease is breast cancer.